Oil and gas furnace



Patented May 19, 1931 FATF.'

ROBERT C. HOPKINS, QF ALLIANCE, OHIO OIL .AND GAS FUE/NACE Application :filed October 9, 1930. Serial No. 487,4718.

, The invention relates to heating furnaces which are preferably oil fired, and more particularly to the furnace wall arrangement and construction at and adjacent the fuel burners, of which there are always at least two.

lt is most desirable in heating furnaces, which for the purpose of description and illustration may be of the drop forge type, such as used for heating blanks for forging, havingthe usual hearth, side wall and roof arrangement, to utilizethe blast issuing from the heating burner to induce a corresponding fiow'of hot gases in the furnace, and to entrain the hot gases in the blast for preheating the air and fuel constituting the blast, just previously to and during combustion of the fuel for obtaining complete combustion 0f the fuel. Single burner iurnaces have been operated in this manner to obtain a flow of hot gases in the furnace induced by the action of the blast, which hot gases mix with the blast for preheating the same.

Such operation of single burner furnaces has in one case required the provision of one or more passageways leading from a part of the heating chamber remote from the burner, back to the burner port where the action of the blast induces a flow of hot gases in the passageways causing a mixing of the hot gases with the blast at and adjacent the burner port.

However, when these passageways are small in cross-sectional area, the flow of hot gases may often be negligible due tov friction losses, particularly when the passageways must traverse a c ircuitous route from a. portion of the heating chamber remote from the burner back to the burner.

On the other hand, when the passageways are suiciently large enough so that friction losses are negligible and so that a substantial flow of hot gasses is present therein, a substantial amount of heat is given up from the het gases to the passageway walls, with the result that, although more eflicient combustion may take place, the heat eciency of the furnace is decreased because a certain amount of the heat has not been usefully used to heat the material in thefurnace, but has been uselessly expended in heating the walls of the passageway. For these reasons such passagcway type furnaces have defeated the purposes for which they were intended and are inefficient.

Single burner furnaces have in another case been designed to accomplish a mixing of het gases with the burner blast by utilizing a quite complicated design of reverberatory heating chamber wherein the gases and blast churn round and round and substantially complete combustion is procured. However, the heating effect on the material in the furnace resulting from the intense heat of radiation of fuel particles at the instant of combustion is lost in this type of furnace because combustion taires place in the adjacent reverberatory proheating chamber, while the heating of the material in the furnace proper is accomplished by the hot gases issuing from the preheating chamber.

rfhus the heating efficiency of this last referred to type of furnace is relatively low notwithstanding the fact that substantially complete combustion has taken place.

ln any event, the furnace construction of each of the two described types of single burner furnaces is very expensive due to the provision of return passageways or fines or of complicatedly designed reverberatory preheating chamber.

Itis therefore one of the objects of the present invention to provide a furnace and burner construction for heating furnaces in which complete combustion will take place, accompanied by a relatively high heating efficiency.

A. further obj ect of the present invention is to provide a furnace construction in which the burner blast will entrain hot gases from the heating chamber both by induction and by a direct pressure flow of the hot gases, for preheating the blast to obtain complete combustion.

A'further object of the present invention is to provide a furnace construction in which the air and fuel blast from the heating burner will be surrounded by a shield or Casing of hot previously burned gases so as to interpose a layer or stratum of inert hot gasesbetween the lire stream and the material being heated in the furnace.

A further object of the present invention is to provide afurnace construction inwhich combustion of the fuel takes place substantially entirely within the Afurnace heating` ychamber' so that 'the material iii the furnace which will bevery inexpensive tocoristruct 'and' maintain.

Y rfhese and other` objects may be attained by providing a furnace'construction, a preferred I embodiment of which'is shown in the drawings and hereinaften described in detail, which may be stated in general terms as including a plurality of burner ports located at opposing'portionsof the furnace, a fuel burner located at each ofthe ports, the longitudinal axis of each of the burners being offset one 'from another, wallsforming aV hot-gas chamber adjacent each burner port, flame ports communicating between each hot-gas cham- Y ber and heating chamber in alignment,V with the respective burnerports, and hot-gas ports communicating between lthe heatingfchamyber and the hot-gaschamber adjacent one lburner and Alocated in the path of the, flame issuing from another burner;

shown inthe accompanying drawings, in

rlhe improved furnaceV construction is which Y Figure 1 isa plan sectional View of the imy proved furnacetaken on the line 1 1, Fig. 2

; provided with an opening 7 for introducing Iintermediately between the hearth 4 and roofV and v Y VFig-.2 is an elevation section of the improved'furii'ace t'alren on the line.2.-2, Fig. 1. Similar numerals refer to similar parts throughout the drawings.

i A. heatingfurnace'is indicated generally at 3, and for the-purposes of illustration'is of a usual drop forge type, and. consists of a hearth wallv 4,'afrear wall 5, a'front wall 6 blanks for.. forging orotherl material to be heated into the furnace, a roof 8 and end walls9. lifdesired any usual and'welllrnown formof doormaybe provided for the open-v ing 7 although ordinarily none is necessary..

Partition walls 10 and 10a areprovided adjacent to and spaced from the end walls?) and form therewith hotfgas chambers indicated at 1.1 and 11a. One ofthe `end walls 9 is provided with a burner port 12 spaced. preferably 8 vandl'ocated-neaie'r the front wall 6 than Vythe rear wall 5, Vwhile'a second burner port 13v Y is provided in the otherend wall 9 spaced intermediately between the roof and 'hearth and locatedvnearer'to ther-ear wall than the i -fro'iit wall 6.

from the burner 14.

burner ports 12 and 13, and each burner has a fuel line connection 15, and an air line con nection 16, whichv are connected with suitable sources of fuel and air under pressure, not shown. Thus, the axis ofthe fuel burner 14 is laterally offset from the axis of the fuel burner 14a. Y l l The partition walls 10 and 10a have Vprof vided therein the enlarged openings or flame ports 17 and 17 a, respectively, the Vflame port 17 being located in alignment with the burner -port 12 and burner 14, and the flame port 17a being located in alignment with the burner port 13 and burner 14a. The flame ports 17 and 17a communicate 'between the liot-gas chambers 11 and 11a, respectively-,and the heating chamber indicated generally at 18;

The partition Awalls 10 and 10a are also provided with hot-gas ports 19 and 19a, respectively, which communicate Vbetween thechambers 11 and11a, respectively, and the yheating chamber 18; the gas port'19 being located in the path ofthe flame issuing from thel burner 14a, and the gas port 19a being located. in the path of the `flame issuing from the burner `14.

ln the operation of the'furnace, air and fuel, which may be'oil, issues in a blast fromV them travel'in the direction of the-arrows shown iii the drawing. and-enter'the hot-gas port 19a into the hot-gas chamber 11a; The fuel and air blast from the burner 14a induces a dow of hot gases from the chamber-11a outward through the flame port 17 aso thatthe hot gases preheat the fuel and air and insure complete combustion and at the. same time envelop the lfueland -air so asV to interpose a layer of hot inert burned gases between the the furnace.

vfire streamand the material being heated in At the same time, the flame from-tlie burner 14a enters the hot-gas port 19 and passes into the hotgas chamber 11 by the pressure of the blast and the liot gases inthe chamber 11 are entrained by Vand surround the blast .issuing Accordingly, complete combustion gtakes place in the furnace chamber with an accompanying high heating efficiency and the furnace construction is of simple design 'and inexpensive to construct and maintain.

j It is pointed out that the fuel utilized may not necessarily be oil, but maybe gas,-tar, or other similar combustible fuel. Y

Likewise, it is not necessary for carrying out the purposes of the present invention that he furnace be rectangulares shown, but the l Y Y v Y same may be round or square. `Fuel burners 14 and 14a are provided at the Moreover, arproper operation of the furnace for carrying out the present invention requires at least two burners and associated burner ports, llame ports, hot-gas chambers and hot-gas ports, but the purposes of the present invention may be carried out equally as well by utilizing more than two burners with their associated ports and chambers so long as the gas port of one chamber is in the path of the flame issuing from another flame port in alignment with another burner and burner port.

I claim l. In furnace wall and heatingchamber construction a plurality of partition walls spaced from the furnace walls to form hotgas chambers, there being a burner port in the furnace walls communicating with each hot-gas chamber, the axes of the burner ports being odset from one another, there being a flame port in each partition wall communieating between the respective hot-gas chamber and the furnace heating chamber and located in alignment with the adjacent burner port, and there being a hot-gas port in each partition wall communicating between the respective hot-gas chamber and furnace heating chamber and located in alignment with the flame port of another hot-gas chamber.

2. ln furnace construction including walls forming a heating chamber, walls spaced from the furnace chamber walls to form two opposed hot-gas chambers, there being burner ports in said spaced walls and a fuel burner for each burner port, the axis of one burner being oliset from the ani-s of the other burner, there being a flame port commu tween each hot-gas chamber and the heating chamber and located in alignment with the respective burner, and there being a hot-gas port communicating between each hot-gas chamber and the heating chamber and located in the path of the flame issuing from the opposed burner.

3. Furnace construction including walls having a plurality of burner ports formed therein and located at opposing portions of the furnace, a fuel burner located at each of the ports, the longitudinal axis of each of the burners being oset from the others, walls forming a hot-gas chamber adjacent each burner port, there being flame ports coinmunicating between each hot-gas chamber and the furnace heating chamber located in alignment with the respective burner ports, and a hot-gas port communicating between the heating chamber and each hot-gas chamber located adjacent one burner and in the path of the flame issuing from another burner.

Il. Furnace construction including a plurality of burners, walls forming a heating chamber and a hot-gas chamber adjacent each burner, there being a burner port to each hotgas chamber and a flame port communicating between each hot-gas chamber and the heatnicating be- 

